Structure and formation method of chip package with fan-out structure

ABSTRACT

Structures and formation methods of a chip package are provided. The method includes forming a protective layer to surround a semiconductor die, and the protective layer has opposing first and second surfaces. The method also includes forming a dielectric layer over the first surface of the protective layer and the semiconductor die. The method further includes forming a conductive feature over the dielectric layer such that the conductive feature is electrically connected to a conductive element of the semiconductor die. In addition, the method includes printing a warpage-control element over the second surface of the protective layer and the semiconductor die such that the semiconductor die is between the warpage-control element and the dielectric layer.

BACKGROUND

The semiconductor integrated circuit (IC) industry has experienced rapidgrowth. Continuing advances in semiconductor manufacturing processeshave resulted in semiconductor devices with finer features and/or higherdegrees of integration. Functional density (i.e., the number ofinterconnected devices per chip area) has generally increased whilefeature size (i.e., the smallest component that can be created using afabrication process) has decreased. This scaling-down process generallyprovides benefits by increasing production efficiency and loweringassociated costs.

A chip package not only provides protection for semiconductor devicesfrom environmental contaminants, but also provides a connectioninterface for the semiconductor devices packaged therein. Smallerpackage structures, which utilize less area or are lower in height, havebeen developed to package the semiconductor devices.

New packaging technologies have been developed to further improve thedensity and functionalities of semiconductor dies. These relatively newtypes of packaging technologies for semiconductor dies facemanufacturing challenges.

BRIEF DESCRIPTION OF THE DRAWINGS

Aspects of the present disclosure are best understood from the followingdetailed description when read with the accompanying figures. It shouldbe noted that, in accordance with the standard practice in the industry,various features are not drawn to scale. In fact, the dimensions of thevarious features may be arbitrarily increased or reduced for clarity ofdiscussion.

FIGS. 1A-1L are cross-sectional views of various stages of a process forforming a chip package, in accordance with some embodiments.

FIGS. 2A-2B are cross-sectional views of various stages of a process forforming a chip package, in accordance with some embodiments.

FIG. 3A is a cross-sectional view of an intermediate stage of a processfor forming a chip package, in accordance with some embodiments.

FIG. 3B is a cross-sectional view of an intermediate stage of a processfor forming a chip package, in accordance with some embodiments.

FIGS. 4A-4C are cross-sectional views of various stages of a process forforming a chip package, in accordance with some embodiments.

FIGS. 5A-5D are top views of chip packages, in accordance with someembodiments.

DETAILED DESCRIPTION

The following disclosure provides many different embodiments, orexamples, for implementing different features of the provided subjectmatter. Specific examples of components and arrangements are describedbelow to simplify the present disclosure. These are, of course, merelyexamples and are not intended to be limiting. For example, the formationof a first feature over or on a second feature in the description thatfollows may include embodiments in which the first and second featuresare formed in direct contact, and may also include embodiments in whichadditional features may be formed between the first and second features,such that the first and second features may not be in direct contact. Inaddition, the present disclosure may repeat reference numerals and/orletters in the various examples. This repetition is for the purpose ofsimplicity and clarity and does not in itself dictate a relationshipbetween the various embodiments and/or configurations discussed.

Further, spatially relative terms, such as “beneath,” “below,” “lower,”“above,” “upper” and the like, may be used herein for ease ofdescription to describe one element or feature's relationship to anotherelement(s) or feature(s) as illustrated in the figures. The spatiallyrelative terms are intended to encompass different orientations of thedevice in use or operation in addition to the orientation depicted inthe figures. The apparatus may be otherwise oriented (rotated 90 degreesor at other orientations) and the spatially relative descriptors usedherein may likewise be interpreted accordingly.

Embodiments of the disclosure may be applied in 3D packaging or 3D ICdevices. Other features and processes may also be included. For example,testing structures may be included to aid in the verification testing ofthe 3D packaging or 3DIC devices. The testing structures may include,for example, test pads formed in a redistribution layer or on asubstrate that allows the testing of the 3D packaging or 3DIC, the useof probes and/or probe cards, and the like. The verification testing maybe performed on intermediate structures as well as the final structure.Additionally, the structures and methods disclosed herein may be used inconjunction with testing methodologies that incorporate intermediateverification of known good dies to increase the yield and decreasecosts.

Some embodiments of the disclosure are described. Additional operationscan be provided before, during, and/or after the stages described inthese embodiments. Some of the stages that are described can be replacedor eliminated for different embodiments. Additional features can beadded to the semiconductor device structure. Some of the featuresdescribed below can be replaced or eliminated for different embodiments.Although some embodiments are discussed with operations performed in aparticular order, these operations may be performed in another logicalorder.

FIGS. 1A-1L are cross-sectional views of various stages of a process forforming a chip package, in accordance with some embodiments. As shown inFIG. 1A, an adhesive layer 102 and a base layer 104 are deposited orlaminated over a carrier substrate 100, in accordance with someembodiments.

In some embodiments, the carrier substrate 100 is used as a temporarysupport substrate. The carrier substrate 100 may be made of asemiconductor material, ceramic material, polymer material, metalmaterial, another suitable material, or a combination thereof. In someembodiments, the carrier substrate 100 is a glass substrate. In someother embodiments, the carrier substrate 100 is a semiconductorsubstrate, such as a silicon wafer.

The adhesive layer 102 may be made of glue, or may be a laminationmaterial, such as a foil. In some embodiments, the adhesive layer 102 isphotosensitive and is easily detached from the carrier substrate 100 bylight irradiation. For example, shining ultra-violet (UV) light or laserlight on the carrier substrate 100 is used to detach the adhesive layer102. In some embodiments, the adhesive layer 102 is alight-to-heat-conversion (LTHC) coating. In some other embodiments, theadhesive layer 102 is heat-sensitive. The adhesive layer 102 may bedetached using a thermal operation.

In some embodiments, the base layer 104 is a polymer layer or apolymer-containing layer. The base layer 104 may be a polybenzoxazole(PBO) layer, a polyimide (PI) layer, a solder resist (SR) layer, anAjinomoto buildup film (ABF), a die attach film (DAF), another suitablelayer, or a combination thereof. In some embodiments, the base layer 104includes multiple sub-layers.

Many variations and/or modifications can be made to embodiments of thedisclosure. In some other embodiments, the base layer 104 is not formed.

Afterwards, a seed layer 106 is deposited over the base layer 104, asshown in FIG. 1A in accordance with some embodiments. In someembodiments, the seed layer 106 is made of a metal material. The metalmaterial may be made of or include titanium (Ti), Ti alloy, copper (Cu),Cu alloy, another suitable material, or a combination thereof. In someother embodiments, the seed layer 106 includes multiple sub-layers.

In some embodiments, the seed layer 106 is deposited using a physicalvapor deposition (PVD) process such as a sputtering process, a chemicalvapor deposition (CVD) process, a spin-on process, another applicableprocess, or a combination thereof.

Many variations and/or modifications can be made to embodiments of thedisclosure. In some other embodiments, the seed layer 106 is not formed.

As shown in FIG. 1B, conductive structures including conductivestructures 112A, 112B, 112C, and 112D are formed, in accordance withsome embodiments. In some embodiments, the conductive structures 112A,112B, 112C, and 112D include conductive pillars. In some embodiments,each of the conductive structures 112A, 112B, 112C, and 112D has alinear sidewall. In some embodiments, the linear sidewall issubstantially perpendicular to a main surface of the base layer 104.

In some embodiments, a mask layer (not shown) is formed over the seedlayer 106 to assist in the formation of the conductive structures112A-112D. The mask layer has multiple openings that expose portions ofthe seed layer 106. The openings of the mask layer define positionswhere the conductive structures will be formed. In some embodiments, themask layer is made of a photoresist material.

In some embodiments, the conductive structures 112A-112D are made of orinclude a metal material. The metal material may include Cu, Ti, gold(Au), cobalt (Co), aluminum (Al), tungsten (W), another suitablematerial, or a combination thereof. In some embodiments, the conductivestructures 112A-112D are made of or include a solder material. Thesolder material may include tin (Sn). In some other embodiments, theconductive structures 112A, 112B, 112C, and 112D are made of a metalmaterial that does not include Sn.

In some embodiments, the conductive structures 112A, 112B, 112C, and112D are formed using a plating process utilizing the seed layer 106.The plating process may include an electroplating process, anelectroless plating process, another applicable process, or acombination thereof.

However, many variations and/or modifications can be made to embodimentsof the disclosure. In some other embodiments, the conductive structures112A, 112B, 112C, and 112D are formed using a chemical vapor deposition(CVD) process, a physical vapor deposition (PVD) process, a spin-onprocess, another applicable process, or a combination thereof.

Afterwards, the mask layer is removed, and the portions of the seedlayer 106 that are not covered by the conductive structures 112A-112Dare removed, as shown in FIG. 1B in accordance with some embodiments. Anetching process may be used to partially remove the seed layer 106. Theconductive structures 112A-112D may function as an etching mask duringthe etching of the seed layer 106.

Many variations and/or modifications can be made to embodiments of thedisclosure. In some other embodiments, the seed layer 106 and/or theconductive structures 112A-112D are not formed.

As shown in FIG. 1C, semiconductor dies including semiconductor dies122A and 122B are attached over the carrier substrate 100, in accordancewith some embodiments. In some embodiments, back sides of thesemiconductor dies 122A and 122B face the base layer 104 with frontsides of the semiconductor dies 122A and 122B facing away therefrom. Anadhesive film 120 may be used to affix the semiconductor dies 122A and122B to the base layer 104. The adhesive film 120 may include a dieattach film (DAF), a glue, or another suitable film.

Each of the semiconductor dies 122A and 122B may include a semiconductorsubstrate 114, a dielectric structure 116, and conductive features 118located at the front side thereof. The dielectric structure 116 mayinclude multiple dielectric layers (not shown). The conductive features118 may be conductive pads. In some embodiments, various device elementsare formed in and/or on the semiconductor substrate 114.

Examples of the various device elements include transistors (e.g., metaloxide semiconductor field effect transistors (MOSFET), complementarymetal oxide semiconductor (CMOS) transistors, bipolar junctiontransistors (BJT), high voltage transistors, high-frequency transistors,p-channel and/or n-channel field effect transistors (PFETs/NFETs),etc.), diodes, or other suitable elements.

The device elements are interconnected to form integrated circuitdevices through conductive features formed in the dielectric structure116. The dielectric structure 116 may include multiple sub-layers. Theconductive features may include multiple conductive lines, conductivecontacts, and conductive vias. In some embodiments, electricalconnections between the conductive features 118 and the device elementsare formed through the conductive features formed in the dielectricstructure 116. In some embodiments, the conductive features 118 aremetal pads which may be made of aluminum or another suitable material.

The integrated circuit devices include logic devices, memory devices(e.g., static random access memories, SRAMs), radio frequency (RF)devices, input/output (I/O) devices, system-on-chip (SoC) devices, otherapplicable types of devices, or a combination thereof. In someembodiments, the semiconductor die 122A or 122B is a system-on-chip(SoC) chip that includes multiple functions.

As shown in FIG. 1D, a protective layer 124 is formed over the carriersubstrate 100 to surround the conductive structures 112A-112D and thesemiconductor dies 122A and 122B, in accordance with some embodiments.In some embodiments, the protective layer 124 covers the sidewalls ofthe conductive structures 112A-112D and the semiconductor dies 122A and122B.

In some embodiments, the protective layer 124 does not cover topsurfaces of the conductive structures 112A-112D and of the semiconductordies 122A and 122B. In some embodiments, the conductive structures112A-112D penetrate through the protective layer 124. The conductivestructures 112A-112D are used as through package vias (TPVs) or throughintegrated fan-out vias (TIVs). In some embodiments, the protectivelayer 124 includes a polymer material. In some embodiments, theprotective layer 124 includes a molding compound material. The moldingcompound material may include an epoxy-based resin with fillersdispersed therein.

In some embodiments, the protective layer 124 is formed by injecting amolding compound material over the carrier substrate 100. In someembodiments, after or during the injecting of the molding compoundmaterial, the molding compound material does not cover the top surfacesof the conductive structures 112A-112D and/or the semiconductor dies122A and 122B.

In some embodiments, a liquid molding compound material is disposed overthe carrier substrate 100 to encapsulate the conductive structures112A-112D and the semiconductor dies 122A and 122B. The liquid moldingcompound material may be made of or include liquid state epoxy resin,liquid state epoxy acrylate, liquid state epoxy resin with filler,liquid state epoxy acrylate with filler, one or more other suitableliquid state materials, or a combination thereof. In some embodiments, athermal process is then applied to harden the liquid molding compoundmaterial and to transform it into the protective layer 124.

In some embodiments, the thermal process is performed at a temperaturein a range from about 200 degrees C. to about 250 degrees C. Theoperation time of the thermal process may be in a range from about 0.5hour to about 3 hours.

In some embodiments, a mold is used to assist in the formation of theprotective layer 124. FIGS. 2A-2B are cross-sectional views of variousstages of a process for forming the protective layer 124 of a chippackage, in accordance with some embodiments.

As shown in FIG. 2A, a mold 200 is disposed over the carrier substrate100, in accordance with some embodiments. In some embodiments, a space230 is formed between the mold 200 and the carrier substrate 100, asshown in FIG. 2A.

In some embodiments, the mold 200 includes a sealing element 201. Thesealing element 201 may be used to cover the peripheral region of thecarrier substrate 100. In some embodiments, the sealing element 201 is asealing ring. The sealing element 201 may also be used as a settlingelement that affixes the carrier substrate 100 under the mold 200.

However, many variations and/or modifications can be made to embodimentsof the disclosure. In some other embodiments, the sealing element 201 isnot formed.

In some embodiments, the mold 200 includes a release film 202. The space230 is surrounded by the carrier substrate 100, the sealing element 201,and the release film 202. In some embodiments, the release film 202 ismade of a material that has a poor adhesion with a material used forforming the protective layer 124. In some embodiments, the release film202 is in direct contact with the conductive structures 112A, 112B,112C, and 112D after the mold 200 is disposed over the carrier substrate100. In some embodiments, the release film 202 is also in direct contactwith the semiconductor dies 122A and 122B.

However, many variations and/or modifications can be made to embodimentsof the disclosure. In some other embodiments, the release film 202 isnot included.

In some embodiments, the mold 200 has one or more openings 206. Each ofthe openings 206 may be used to allow a molding compound material 204 tobe injected into the mold 200. In some embodiments, one or more of theopenings 206 are used to allow the molding compound material 204 to flowout of the mold 200. In some embodiments, each of the openings 206 isused for letting the molding compound material 204 flow into the mold200. In some other embodiments, the mold 200 has only one opening 206that allows the molding compound material 204 to flow into the space230.

Afterwards, the molding compound material 204 is injected into the space230 between the mold 200 and the carrier substrate 100 until the moldingcompound material 204 completely fill the space 230, as shown in FIG.2B, in accordance with some embodiments. The conductive structures112A-112D are surrounded by the molding compound material 204. Thesemiconductor dies 122A and 122B are also surrounded by the moldingcompound material 204, as shown in FIG. 2B in accordance with someembodiments.

In some embodiments, the release film 202 is in direct contact with theconductive structures 112A, 112B, 112C, and 112D during the injecting ofthe molding compound material 204. In some embodiments, the release film202 is also in direct contact with the semiconductor dies 122A and 122Bduring the injecting of the molding compound material 204.

Afterwards, the molding compound material 204 is cured to become theprotective layer 124, and the mold 200 is then removed, as shown in FIG.1D in accordance with some embodiments. In some embodiments, the moldingcompound material 204 is cured to form the protective layer 124 beforethe removal of the mold 200.

Many variations and/or modifications can be made to embodiments of thedisclosure. In some other embodiments, a first thermal operation isperformed before the removal of the mold 200, followed by a secondthermal operation performed after the removal of the mold 200. The firstthermal operation is performed at a lower temperature than the secondthermal operation. The second thermal operation is used to complete thecuring of the molding compound material 204 after the mold 200 isremoved. As a result, the protective layer 124 is formed.

In some embodiments, during the injecting of the molding compoundmaterial 204, the molding compound material 204 does not cover the topsurfaces of the conducting structures 112A-112D and/or the semiconductordies 122A and 122B due to the mold 200. As a result, the top surfaces ofthe conducting structures 112A-112D and the semiconductor dies 122A and122B are not covered by the protective layer 124, as shown in FIG. 1D.In some embodiments, it is not necessary for the protective layer 124 tobe thinned since the conductive structures 112A-112D and the conductivefeatures 118 of the semiconductor dies 122A and 122B have been exposedwithout being covered by the protective layer 124.

In some embodiments, since no thinning process on the protective layer124 is required, fabrication cost and processing time are reduced.Damage due to the thinning process may also be prevented. In someembodiments, no additional passivation layer or conductive pillars needsto be formed on the semiconductor dies, and so the fabrication cost andprocessing time are reduced further.

In some embodiments, the adhesion between the molding compound material204 and the release film 202 is poor. Therefore, the molding compoundmaterial 204 may be prevented from adhering on the mold 200 during thesubsequent removal of the mold 200. After the removal of the mold 200,recesses may be formed at the surface of the molding compound material204. As a result, there are also some recesses 126 formed at the surfaceof the protective layer 124 after the molding compound material 204 iscured to form the protective layer 124.

As shown in FIG. 1D, the protective layer 124 has recesses 126, inaccordance with some embodiments. Some of the recesses 126 are adjacentto the semiconductor die 122A or 122B. Some of the recesses 126 arebetween the semiconductor die 122A or 122B and one of the conductivestructures 112A, 112B, 112C, and 112D. Some of the recesses 126 arebetween two of the conductive structures, such as between the conductivestructures 112B and 112C. As shown in FIG. 1D, one of the recesses 126has a depth D. In some embodiments, the depth D is in a range from about3 μm to about 10 μm. For example, the depth D may be about 7 μm.

As shown in FIG. 1E, a dielectric layer 128 a is formed over theprotective layer 124, the conductive structures 112A-112D, and thesemiconductor dies 122A and 122B. In some embodiments, the dielectriclayer 128 a fills the recesses 126 of the protective layer 124. In someembodiments, the dielectric layer 128 a is made of or includes one ormore polymer materials. The dielectric layer 128 a may be made of orinclude polybenzoxazole (PBO), polyimide (PI), another suitablematerial, or a combination thereof. In some embodiments, the dielectriclayer 128 a is formed using a spin coating process, a spray coatingprocess, another applicable process, or a combination thereof.

As shown in FIG. 1E, the dielectric layer 128 a is patterned to formmultiple openings 129, in accordance with some embodiments. In someembodiments, some of the openings 129 correspondingly expose theconductive structures 112A-112D. In some embodiments, some of theopenings 129 correspondingly expose the conductive features 118 of thesemiconductor dies 122A and 112B. In some embodiments, the openings 129are formed using a photolithography process, a laser drilling process,an etching process, another applicable process, or a combinationthereof.

Afterwards, conductive layers 130 a are formed over the dielectric layer128 a, as shown in FIG. 1F in accordance with some embodiments. In someembodiments, each of the conductive layers 130 a fills the correspondingopening 129. In some embodiments, each conductive structure 112A to 112Dis electrically connected to a corresponding one of the conductivelayers 130 a through a corresponding one of the openings 129. In someembodiments, each conductive feature 118 (such as a conductive pad) ofthe semiconductor die 122A is electrically connected to a correspondingone of the conductive layers 130 a through a corresponding one of theopenings 129. In some embodiments, the conductive structure 112A iselectrically connected to one of the conductive features 118 of thesemiconductor die 122A through the corresponding one of the conductivelayers 130 a.

Referring to FIG. 1G, a dielectric layer 128 b is formed over thedielectric layer 128 a and the conductive layers 130 a, in accordancewith some embodiments. In some embodiments, the material and formationmethod of the dielectric layer 128 b is the same as or similar to thoseof the dielectric layer 128 a.

However, embodiments of the disclosure are not limited thereto. In someother embodiments, the dielectric layer 128 b is made of a differentdielectric material than the dielectric layer 128 a. In someembodiments, the dielectric layer 128 b is made of silicon oxide or thelike using a deposition process, such as a chemical vapor deposition(CVD) process.

Afterwards, multiple dielectric layers including a dielectric layer 128c and a passivation layer 132 and multiple conductive layers includingconductive layers 130 b and 130 c are formed, as shown in FIG. 1G inaccordance with some embodiments. In some embodiments, conductive bumps134 are formed. An under bump metallurgy (UBM) layer (not shown) may beformed between the conductive bumps 134 and the conductive layers 130 c.

Afterwards, the structure shown in FIG. 1G is placed upside down on acarrier tape 240, as shown in FIG. 1H in accordance with someembodiments. The carrier substrate 100 and adhesive layer 102 areremoved, as shown in FIG. 1H. The carrier substrate 100 and adhesivelayer 102 may be removed using a light irradiation operation, a thermaloperation, another applicable operation, or a combination thereof.

As shown in FIG. 1I, multiple conductive bumps 142 are formed over theprotective layer 124, in accordance with some embodiments. In someembodiments, the conductive bumps 142 are made of or include a soldermaterial. The solder material may include tin and other metal materials.In some embodiments, the conductive bumps 142 are made of or includecopper, gold, aluminum, titanium, cobalt, platinum, another suitablematerial, or a combination thereof.

In some embodiments, multiple openings are formed in the base layer 104.Some or all of the openings expose the remaining seed layer 106 on theconductive structures such as 112A, 112B, 112C, and 112D. The remainingseed layer 106 and the conductive structures 112A, 112B, 112C, and 112Dtogether form conductive pillars. Afterwards, one or more conductivematerials are formed in the openings to form the conductive bumps 142,as shown in FIG. 1I. The conductive materials may be formed using anelectroplating process, an electroless plating process, a printingprocess, another applicable process, or a combination thereof.

Afterwards, warpage-control elements are formed over the base layer 104to prevent or to compensate for the warpage that occurs during theformation of the chip package. In some embodiments, the warpage-controlelements are in direct contact with the base layer 104. In someembodiments, the warpage-control elements are formed using a printingprocess, a dispensing process, another applicable process, or acombination thereof.

As shown in FIG. 1J, a stencil (or a mask) 150 is placed over the baselayer 104 and the conductive bumps 142, in accordance with someembodiments. The stencil 150 has openings that are used to definepatterns of warpage-control elements that will be formed later.

Afterwards, a squeegee 154 is used to move a warpage-control material152 into the openings of the stencil 150, as shown in FIG. 1J inaccordance with some embodiments. Therefore, the warpage-controlmaterial 152 is printed thereon.

In some embodiments, the warpage-control material 152 is made of orincludes a polymer-containing material. The polymer-containing materialmay be in a liquid state. In some embodiments, the polymer-containingmaterial includes an epoxy-based resin, a PBO-containing material,another suitable material, or a combination thereof. In someembodiments, the warpage-control material 152 is similar to or the sameas an underfill material. In some embodiments, the warpage-controlmaterial 152 includes a polymer-containing material and fillersdispersed in the polymer-containing material. The fillers may includeinsulating fibers, insulating particles, other suitable elements, or acombination thereof.

In some embodiments, the warpage-control material 152 further includesone or more pigments. For example, a black pigment is added in thepolymer-containing material. In some embodiments, the base layer 104 hasa greater light transmittance than that of the warpage-control material152. In some embodiments, the base layer 104 has a greater lighttransmittance than that of the warpage-control elements 152′ formed fromthe warpage-control material 152. In some embodiments, the base layer104 has a greater light transmittance than that of the protective layer124.

Many variations and/or modifications can be made to embodiments of thedisclosure. In some other embodiments, the warpage-control material 152is applied over the base layer 104 using another applicable processother than the printing process. For example, the warpage-controlmaterial 152 (such as the polymer-containing material) is applied usinga dispensing process.

As shown in FIG. 1K, after the printing process, the warpage-controlelements 152′ are formed, in accordance with some embodiments. Thewarpage-control elements 152′ are used to prevent or compensate for thewarpage of the structure shown in FIG. 1K. In some embodiments, some orall of the warpage-control elements 152′ are not in direct contact withthe conductive bumps 142.

In some embodiments, a curing operation is used to transform the printedwarpage-control material 152 into warpage-control elements 152′. In someembodiments, the curing operation includes a thermal operation. In someembodiments, the curing temperature of the curing operation is in arange from about 100 degrees C. to about 300 degrees C. In some otherembodiments, the curing temperature of the curing operation is in arange from about 180 degrees C. to about 250 degrees C. In someembodiments, the operation time of the curing process is in a range from30 minutes to about 2 hours. In some other embodiments, the curingoperation includes a light irradiation operation. During the curingoperation, the warpage is prevented or compensated for. As a result, astructure that has substantially no warpage is obtained.

In some embodiments, the warpage-control elements 152′ are obtained fromcuring the printed warpage-control material 152 other than beingprovided as a preformed film or tape. Fabrication costs regarding theexpensive tapes and the lamination tools are prevented or reduced.Fabrication time is also reduced accordingly. In some embodiments, thewarpage-control elements 152′ are formed using a printing process, whichallows the conductive bumps 142 to be formed before the warpage-controlelements 152′. The process for forming the chip package becomesrelatively easy to perform according to these embodiments.

Afterwards, a dicing process (or a cutting operation) is performed toseparate the structure as shown in FIG. 1K into multiple chip packages,as shown in FIG. 1L in accordance with some embodiments. As a result, achip package with a fan-out structure is formed. In some embodiments,the carrier tape 240 is removed after the dicing process. In someembodiments, the top surface of the warpage-control element 152′ islower than the top points of the conductive bumps 142.

In some embodiments, one or more elements are stacked on or bonded ontothe structure as shown in FIG. 1K before the dicing process or onto thestructure as shown in FIG. 1L after the dicing process. As shown in FIG.1L, the element mentioned above (such as an element 170) is stacked overchip package, in accordance with some embodiments. The element 170 mayinclude another chip package, a semiconductor die, one or more passivedevices, another suitable structure, or a combination thereof.

However, embodiments of the disclosure are not limited thereto. In someother embodiments, the element 170 is not formed or stacked.

In some embodiments, the conductive bumps 142 form electricalconnections between the element 170 and the semiconductor die 122A. Theconductive bumps 142 may be bonded to one or more conductive feature ofthe element 170.

Many variations and/or modifications can be made to embodiments of thedisclosure. In some embodiments, the element 170 is stacked before thedicing process. In some other embodiments, the element 170 is stackedafter the dicing process.

In the embodiments illustrated in FIGS. 1A-1L, the warpage-controlelements 152′ are separated from the conductive bumps 142. However,embodiments of the disclosure are not limited thereto. FIG. 3A is across-sectional view of an intermediate stage of a process for forming achip package, in accordance with some embodiments. In some embodiments,the warpage-control elements 152′ are in direct contact with theconductive bumps 142. In some embodiments, the warpage-control elements152′ continuously and/or completely surround the conductive bumps 142.In some embodiments, by modifying the openings of the stencil 150, thepatterns and/or the positions of the warpage-control elements 152′ aremodified accordingly.

Many variations and/or modifications can be made to embodiments of thedisclosure. FIG. 3B is a cross-sectional view of an intermediate stageof a process for forming a chip package, in accordance with someembodiments. In some embodiments, some of the conductive bumps 142 arenot continuously and/or completely surrounded by the warpage-controlelements 152′, as shown in FIG. 3B. In some embodiments, one of thewarpage-control elements 152′ is in direct contact with a side S1 of oneof the conductive bumps 142 while an opposite side S2 of the conductivebump 142 is not in direct contact with the warpage-control elements152′, as shown in FIG. 3B.

In the embodiments illustrated in FIGS. 1A-1L, the conductive bumps 142are formed before the formation of the warpage-control elements 152′.However, many variations and/or modifications can be made to embodimentsof the disclosure. In some other embodiments, the conductive bumps 142are formed after the formation of the warpage-control elements 152′.

FIGS. 4A-4C are cross-sectional views of various stages of a process forforming a chip package, in accordance with some embodiments. As shown inFIG. 4A, a structure similar to or the same as that shown in FIG. 1H isreceived or formed. Afterwards, the warpage-control elements 152′ areformed over the base layer 104, as shown in FIG. 4A in accordance withsome embodiments. The material and formation method of thewarpage-control elements 152′ shown in FIG. 4A may be similar to or thesame as those of the warpage-control elements 152′ illustrated in FIGS.1J-1K.

As shown in FIG. 4B, openings 402 are formed in the base layer 104 toexpose the conductive pillars constructed by the seed layer 106 and theconductive structures 112A-112D, in accordance with some embodiments.The openings 402 may be formed using a photolithography process, a laserdrilling process, an etching process, a mechanical drilling process,another applicable process, or a combination thereof.

In some embodiments, the warpage-control elements 152′ do not cover theconductive pillars construed by the seed layer 106 and the conductivestructures 112A-112D. Therefore, during the formation of the openings402, the positions of the conductive pillars can be observed or detectedsince the base layer 104 has relatively high light transmittance. Thealignments between the openings 402 and the conductive pillars arerelatively easy to be achieved. In some other cases where a warpage tapeis used, misalignments between the openings 402 and the conductivepillars might occur since the warpage tape having a low lighttransmittance covers the conductive pillars.

Many variations and/or modifications can be made to embodiments of thedisclosure. In some other embodiments, the warpage-control elements 152′are formed after the formation of the openings 402.

As shown in FIG. 4C, the conductive bumps 142 are formed to fill theopenings 402, in accordance with some embodiments. The material andformation method of the conductive bumps 142 shown in FIG. 4C may besimilar to or the same as those of the conductive bumps 142 illustratedin FIG. 1I.

FIG. 5A is a top view of a chip package, in accordance with someembodiments. In some embodiments, FIG. 5A shows the top view of a chippackage similar to that shown in FIG. 1L. For clarity, the element 170is not shown. In some other embodiments, the element 170 is not formed.

In some embodiments, the chip package includes only one warpage-controlelement 152′. In some other embodiments, the chip package includesmultiple warpage-control elements 152′ that are separated from eachother. In some embodiments, the warpage-control element 152′ isseparated from the conductive bumps 142 without fully surrounding theconductive bumps 142. In some embodiments, the conductive bumps 142surround or encircle the warpage-control element 152′.

In FIG. 5A, since the semiconductor die 122A is covered by the baselayer 104, dashed lines are used to illustrate the position and profileof the semiconductor die 122A. In some embodiments, the warpage-controlelement 152′ has a greater area than that of the semiconductor die 122A.As shown in FIG. 5A, the semiconductor die 122A is covered by thewarpage-control element 152′.

FIG. 5B is a top view of a chip package, in accordance with someembodiments. In some embodiments, some of the conductive bumps 142 arepartially surrounded by the warpage-control element 152′. A portion ofthe warpage-control element 152′ extends between two adjacent conductivebumps 142.

FIG. 5C is a top view of a chip package, in accordance with someembodiments. In some embodiments, the conductive bumps 142 are not onlypositioned on periphery portions of the base layer 104. Some of theconductive bumps 142 are positioned on the semiconductor die 122A. Someof the conductive bumps 142 cover the semiconductor die 122A. Forexample, when the size of the semiconductor die 122A is relatively smallor the number of the conductive bumps 142 to be provided in the chippackage is a lot, some of the conductive bumps 142 may be positioneddirectly above the semiconductor die 122A. In some embodiments, thewarpage-control element 152′ is separated from the conductive bumps 142.In some embodiments, some of the conductive bumps 142 are continuouslyand/or completely surrounded by the warpage-control element 152′, asshown in FIG. 5C.

FIG. 5D is a top view of a chip package, in accordance with someembodiments. In some embodiments, the warpage-control element 152′partially surrounds the conductive bumps 142. In some embodiments, thewarpage-control element 152′ is in direct contact with some of theconductive bumps 142. In some embodiments, inner sides S1′ of theconductive bumps 142 facing a center of the chip package are in directcontact with the warpage-control element 152′. Outer sides S2′ of theconductive bumps 142 are not in direct contact with the warpage-controlelement 152′, as shown in FIG. 5D.

Many variations and/or modifications can be made to embodiments of thedisclosure. In some embodiments, the warpage-control element 152′ coversthe entire top surface of the base layer 104. In these cases, theconductive bumps 142 surrounded by the warpage-control element 152′.

Embodiments of the disclosure form a chip package having a semiconductordie surrounded by a protective layer. One or more warpage-controlelements are printed over (but are not laminated over) the protectivelayer to prevent or compensate for the warpage of the chip package.Fabrication cost and processing time due to the warpage tape laminationare prevented or reduced. The position and pattern of thewarpage-control element can be controlled more easily, which facilitatessubsequent processes including the formation of the conductive bumps.The performance and quality of the chip package are significantlyimproved.

In accordance with some embodiments, a method for forming a chip packageis provided. The method includes forming a protective layer to surrounda semiconductor die, and the protective layer has opposing first andsecond surfaces. The method also includes forming a dielectric layerover the first surface of the protective layer and the semiconductordie. The method further includes forming a conductive feature over thedielectric layer such that the conductive feature is electricallyconnected to a conductive element of the semiconductor die. In addition,the method includes printing a warpage-control element over the secondsurface of the protective layer and the semiconductor die such that thesemiconductor die is between the warpage-control element and thedielectric layer.

In accordance with some embodiments, a method for forming a chip packageis provided. The method includes forming multiples conductive pillarsand disposing multiple semiconductor dies over a carrier substrate. Themethod also includes forming a protective layer over the carriersubstrate to surround the conductive pillars and the semiconductor dies.The method further includes forming a dielectric layer over theprotective layer, the conductive pillars, and the semiconductor dies. Inaddition, the method includes forming first conductive bumps over thedielectric layer and removing the carrier substrate. The method includesforming second conductive bumps over the protective layer, and the firstconductive bumps and the second conductive bumps are positioned overopposite sides of the protective layer. The method also includes formingwarpage-control elements over the protective layer.

In accordance with some embodiments, a chip package is provided. Thechip package includes a semiconductor die and a protective layersurrounding the semiconductor die. The chip package also includes aconductive pillar penetrating through the protective layer and separatedfrom the semiconductor die by the protective layer. The chip packagefurther includes a conductive bump and a warpage-control element over asame side of the protective layer. The conductive bump is electricallyconnected to the conductive pillar, and the warpage-control element isseparated from the conductive bump.

The foregoing outlines features of several embodiments so that thoseskilled in the art may better understand the aspects of the presentdisclosure. Those skilled in the art should appreciate that they mayreadily use the present disclosure as a basis for designing or modifyingother processes and structures for carrying out the same purposes and/orachieving the same advantages of the embodiments introduced herein.Those skilled in the art should also realize that such equivalentconstructions do not depart from the spirit and scope of the presentdisclosure, and that they may make various changes, substitutions, andalterations herein without departing from the spirit and scope of thepresent disclosure.

What is claimed is:
 1. A method for forming a chip package, comprising:forming a protective layer to surround a semiconductor die, wherein theprotective layer has opposing first and second surfaces; forming adielectric layer over the first surface of the protective layer and thesemiconductor die; forming a conductive feature over the dielectriclayer such that the conductive feature is electrically connected to aconductive element of the semiconductor die; disposing apolymer-containing material to partially cover the second surface of theprotective layer; and curing the polymer-containing material to form awarpage-control element over the second surface of the protective layerand the semiconductor die such that the semiconductor die is between thewarpage-control element and the dielectric layer.
 2. The method forforming a chip package as claimed in claim 1, further comprising:disposing a mold over the semiconductor die; injecting a moldingcompound material into the mold to surround the semiconductor die;curing the molding compound material to form the protective layer; andremoving the mold.
 3. The method for forming a chip package as claimedin claim 1, further comprising forming a conductive bump over the secondsurface of the protective layer, wherein the conductive bump iselectrically connected to a second conductive element of thesemiconductor die, and the warpage-control element is not in directcontact with the conductive bump.
 4. The method for forming a chippackage as claimed in claim 1, further comprising: forming a conductivepillar beside the semiconductor die before the protective layer isformed; placing a stencil over the second surface of the protectivelayer to cover the conductive pillar; printing a polymer-containingmaterial over the protective layer through openings of the stencil; andcuring the polymer-containing material to form the warpage-controlelement.
 5. The method for forming a chip package as claimed in claim 4,further comprising forming a conductive bump on the conductive pillarafter the warpage-control element is formed.
 6. The method for forming achip package as claimed in claim 1, further comprising forming aconductive bump over the second surface of the protective layer.
 7. Themethod for forming a chip package as claimed in claim 6, wherein theconductive bump is formed before the warpage-control element is formed.8. The method for forming a chip package as claimed in claim 7, furthercomprising: placing a stencil over the second surface of the protectivelayer to cover the conductive bump; printing a polymer-containingmaterial over the protective layer through openings of the stencil; andcuring the polymer-containing material to form the warpage-controlelement.
 9. The method for forming a chip package as claimed in claim 7,further comprising: placing a stencil over the second surface of theprotective layer to partially cover the conductive bump; printing apolymer-containing material over the protective layer through openingsof the stencil; and curing the polymer-containing material to form thewarpage-control element, wherein the warpage-control element is indirect contact with the conductive bump.
 10. A method for forming a chippackage, comprising: forming a plurality of conductive pillars anddisposing a plurality of semiconductor dies over a carrier substrate;forming a protective layer over the carrier substrate to surround theconductive pillars and the semiconductor dies; forming a dielectriclayer over the protective layer, the conductive pillars, and thesemiconductor dies; forming a plurality of first conductive bumps overthe dielectric layer; removing the carrier substrate; forming aplurality of second conductive bumps over the protective layer, whereinthe first conductive bumps and the second conductive bumps arepositioned over opposite sides of the protective layer; and forming aplurality of warpage-control elements over the protective layer.
 11. Themethod for forming a chip package as claimed in claim 10, furthercomprising performing a cutting operation to the protective layer toform a plurality of chip packages, wherein one of the chip packagescomprises one of the semiconductor dies and one of the warpage-controlelements.
 12. The method for forming a chip package as claimed in claim10, wherein the second conductive bumps are formed before thewarpage-control elements are printed.
 13. The method for forming a chippackage as claimed in claim 10, further comprising: disposing a moldover the carrier substrate to surround a space; injecting a moldingcompound material into the space to surround the semiconductor dies andthe conductive pillars; curing the molding compound material to form theprotective layer; and removing the mold.
 14. The method for forming achip package as claimed in claim 10, further comprising forming a baselayer over the carrier substrate before the conductive pillars areformed, wherein the base layer has a greater light transmittance thanthat of each of the warpage-control elements.
 15. The method for forminga chip package as claimed in claim 14, further comprising forming aplurality of openings in the base layer to expose the conductive pillarsafter the carrier substrate is removed, wherein the second conductivebumps fill the openings.
 16. A chip package, comprising: a semiconductordie; a protective layer surrounding the semiconductor die; a conductivepillar penetrating through opposite surfaces of the protective layer andseparated from the semiconductor die by the protective layer; and aconductive bump and a warpage-control element over a same side of theprotective layer, wherein the conductive bump is electrically connectedto the conductive pillar, and the warpage-control element is separatedfrom the conductive bump, a top surface of the warpage-control elementis higher than a bottom surface of the conductive bump, and the topsurface of the warpage-control element is lower than a top surface ofthe conductive bump.
 17. The chip package as claimed in claim 16,further comprising a base layer over the protective layer, wherein thebase layer surrounds a portion of the conductive bump, and the baselayer is between the warpage-control element and the semiconductor die.18. The chip package as claimed in claim 17, wherein the base layer hasa greater light transmittance than that of the warpage-control element.19. The chip package as claimed in claim 17, wherein the warpage-controlelement has a greater area than that of the semiconductor die.
 20. Thechip package as claimed in claim 16, further comprising a secondsemiconductor die stacked over the semiconductor die, wherein thewarpage control element is between the semiconductor die and the secondsemiconductor die.